Nine people were arrested in Seattle Sunday after protests in the city, calling for better wages for workers, an end to deportations and support for an Obama administration plan to give work permits to immigrants in the country, turned violent. Clashes between Seattle police and anti-capitalist demonstrators began after a peaceful march by advocates for workers and immigrants, according to media reports.

Hundreds of families, students and activists were part of the march that was permitted by authorities. However, the May Day gathering turned unruly after demonstrators threw rocks, bricks and Molotov cocktails at officers. Five officers were injured and were being treated, the Associated Press (AP) reported, adding that police used pepper spray to disperse the crowd. The anti-capitalist demonstrators, who did not have a permit from city officials, carried signs that read: "We Are Ungovernable."

The Seattle police said that the protesters were arrested on charges of property destruction, assault and obstruction. Eight male and one juvenile female were among those arrested Sunday.

"Seattle Police Department supports peaceful protest, but has zero tolerance for any acts of violence towards persons, police and property,” Seattle Police Chief Kathleen O'Toole said in a statement. 

"This is no longer a peaceful march," Steve Wilske, Seattle Police assistant chief, earlier said on Twitter. Police posted a photo of some weapons seized during protests Sunday on its Twitter account.

"Upon determining that the crowd presents an imminent risk to public safety or that large-scale property destruction appears likely authorities ordered protesters to disperse," Seattle police said, in a statement.

The May Day gatherings in Seattle every year witness some disruptions. Last year, police reportedly arrested 16 people during demonstrations and in 2014, 10 people were arrested. In 2013, police arrested 18 people who pelted rocks and bottles at officers.